Airlines will be required to give flight attendants at least 10 hours off duty between shifts, one more hour than currently, under a rule announced Tuesday by the Federal Aviation Administration.
Acting FAA Administrator Billy Nolen said that the extra hour of rest would contribute to safety.
The rule goes into effect in 30 days, and airlines have up to 90 days to comply.
Congress directed the FAA in 2018 to increase the rest requirement for flight attendants and eliminate a provision that let crews work with less rest under some circumstances.
"It took us way too long, but we are finally here," Nolen said at a news conference at Reagan Washington National Airport, where he was flanked by more than a dozen flight attendants.